Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for New Castle can be read to determine when it's possible to plant romanesco.

Planting Calendar for Romanesco

Frost tolerance for romanesco:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Romanesco tend to make it in moderate cold which tells us that you can plant them just a bit earlier in the year than more sensitive plants.

The earliest that you can plant romanesco in New Castle is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant romanesco and expect a good harvest is probably September. Any later than that and your romanesco may not have a chance to grow to maturity. Starting your romanesco indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in New Castle. You can expect an average low temperature of -15°F in the coldest months of winter.

It's important to remember that the actual date of last frost is an average because it is based on the USDA zone info for New Castle and it will vary from year to year. Half of the time in New Castle there is a last frost after April 15 so make sure that you are prepared to cover your romanesco if you have a late frost.

USDA Zone Info for New Castle

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in New Castle

You may be interested in your other planting guides for New Castle.